The invention relates to the manufacture of starting motors for passenger vehicle internal combustion engines and, more particularly, to a method and apparatus for converting an engine starting motor from one engine installation for use in a different engine installation.
Internal combustion engines used in passenger vehicles, such as cars or trucks, are generally started by rotating the flywheel until the engine fires and continues to run on its own power. The flywheel is usually rotated by a starting motor fed with current from the battery. The electric starting motor contains a rotatable driveshaft over which is slidably disposed a pinion gear wheel which, on commencement of the starting operation, is shifted forward until it engages with the toothed rim of the flywheel. The driving motor of the starter then rotates its shaft which rotates the flywheel. When the engine has started up, the pinion is retracted and disengaged from the flywheel.
Although other types of electric starting motors are available, most, if not all, present-day internal combustion vehicles utilize an inertia gear drive or Bendix type starter. The Bendix starter includes a main casing shell for containing an electric motor, including a rotary armature mounted concentrically on a driveshaft. Mounted adjacent the casing shell is a smaller cylindrical housing containing a solenoid switch mechanism including a reciprocable armature. In this type of starter, the pinion is carried on a sleeve which can be shifted back and forth along the driveshaft on a quick screw thread. A hollow housing end cap is positioned across adjacent parallel-facing open ends of the solenoid housing and motor shell. The end cap contains a pivotable trigger lever connected at respective opposed ends with the solenoid armature and the pinion sleeve. During car steering operation, the operator turns a key in the ignition activating a starting circuit which establishes electrical connection between the battery and the solenoid switch. A powerful magnetic field is set up in the solenoid switch which attracts the solenoid armature, pulling the solenoid armature rearward against the bias of a return spring force and with it the corresponding end of the trigger level. The opposed end of the trigger lever is then pivoted forward, pushing forward the pinion sleeve as it rotates about the screw thread formed on the driveshaft. The solenoid switch then closes and current flows to a commutator which causes rotation of the motor armature. As the motor armature begins to rotate, the pinion sleeve is screwed completely forward until the pinion engages with the gear rim on the flywheel. The solenoid switch is held in its closed position by a holding coil and the starting motor can now turn the engine. When the engine fires, the starting circuit is deactivated by the operator, such that the solenoid armature thrust forwardly under the force of the return spring. This brings the trigger lever back to the home position such that the pinion sleeve is also returned and the pinion is out of driving engagement with the flywheel.
Although most, if not all, automobiles utilize a Bendix type starter, individual car manufacturers, such as Ford, Chrysler, and Volkswagen, provide their cars with unique starting motor mountings, including housing configurations, spacial dimensions, and support brackets, and have individual starting motor power factors. This situation usually necessitates replacement of a vehicle starting motor with a duplicate purchased from the auto manufacturer, since the starting motor from a different auto manufacturer does not typically have mounting requirements suitable to replace the starting motor in the car built by another manufacturer. Accordingly, the cost to a purchaser for replacing a starting motor results is substantially higher, allowing for profit, then the production cost to manufacture an original starter. However, a tremendous number of cars which are junked contain starting motors in good working order. Prior to this invention these motors had little value being limited for installation only in cars of the same make and most probably also of the same vintage. Thus, if a generalized manufacturing arrangement could be devised which would adapt the starting motors from junked cars of one manufacture to fit starter mounting requirements for cars of other manufacturers, rebuilt starting motors could be purchased to replace original defective starting motors. Because the rebuilt starters are made from low cost used originals, these replacement starters can be sold at a relatively much reduced price, saving the puchaser on the order of about 50 percent or more to replace a starting motor.
The invention is directed to a method and apparatus for adapting starting motors from one vehicle manufacturer to meet the mounting requirements for starters in vehicles of different manufacturers, thus enabling a cost savings to purchasers of replacement starters and affording a competitive market with auto manufacturers in the field of replacement starting motors.